FURY MAZDA doesn't care about some of their clients

I am a first time buyer of a vehicle, I went with a colleague who promised to assist as he knew someone at the dealership, we went to buy the vehicle in the beginning of May, 2022, I was excited and all and really should have taken more time, in understanding what I was getting myself into but I didn't get that they just wanted to make a sale off me, however I didn't see the car until after signing the papers, I realized the maintenance plan is ending and service plan the following year, I was never consulted about the types of interest rates I wanted, I didn't even know it had a balloon payment (as the last time we spoke I told them to add a R30k balloon but they made it 30%), I asked them to use the 15th as a payment date but they are it the 1st and had to struggle to change it, they even brought their lawyers but failed because they didn't read the contract, they constructed a deal and communicated with my colleague as if they were communicating with me, I know I have signed but I thought as a first timer they would ask me or anything but they never did, now I'm fighting to lower the short fall and trade in the car as I can't afford to have a bad record and get the car repossessed, but honestly I'll never go back to FURY MAZDA FOURWAYS ever again, I regret my decision everyday but atleast driving the car makes me forget about the situation. I hope to find a dealership that will respect me and my money, FURY is a no go unless you're friendly with the managers and owners